1. Field of the Invention
The present invention relates to image forming apparatus such as electrophotographic copiers, printers, word processors, facsimile machines, and so on for forming an image on a recording medium and, more particularly, to image forming apparatus equipped with an interface portion.
2. Description of the Related Art
A laser printer will be described below as an example of the image forming apparatus adopting the electrophotographic method and other recording methods.
FIG. 10 is a sectional view of a conventional laser beam printer, in which a recording material is conveyed almost horizontally from sheet feeding means 102 via transferring means 109 to fixing means 111, in which there are provided image forming means including a process cartridge 107 and others and light source means 105 including a laser scanner and others above the conveyed surface of the recording material, and which is constructed to feed the recording material, transfer a toner image onto the recording material, and thermally fix the toner image on the recording material.
Further, an electrical portion 115, in which power supplies for supplying AC, DC, and a high voltage for the apparatus and a control circuit for controlling the operation of the entire apparatus are integrated, is located in the lower part of the apparatus, and is connected through connectors 115a and 130c to an interface portion 130 for exchanging image signals with a computer or a network outside the apparatus through cable 132 so as to process or prepare image data. The image data processed and prepared at this interface portion 130 is sent via the electrical portion 115 to the light source means 105 connected through cable 118, whereby a photosensitive body 108 is exposed to scanning light modulated according to the image data to form a latent image thereon.
FIG. 11 is another sectional view obtained at another position in a direction normal to the plane of the drawing in FIG. 10 and shows a mounted state of an add-on such as a memory card 133 or the like on the interface portion 130. The user is allowed to open an access cover 134, provided on the back side of an exterior housing 113, around a hinge shaft 134a and load or unload the memory card 133 through an aperture 113a onto or out of the interface portion 130.
The user can also mount or dismount a process cartridge 107 by opening a door 116 around a shaft 116a, as shown in FIG. 12.
At this time, in order to protect the user, supply of power from the electrical portion 115 is halted in synchronism with the opening action of the door 116 by an unrepresented interlock mechanism.
However, the conventional image forming apparatus as shown in FIGS. 10 to 12 involves a possibility that the loading/unloading work of the add-on is carried out even during supply of power in the main body of the apparatus, so that the interface portion 130 can be electrically broken during the work. In order to avoid it, it was necessary to provide an interlock switch interlocked with the access cover, in addition to the interlock mechanism interlocked with the opening/closing action of the door 116, and this resulted in the disadvantage of cost increase.
There was another problem of poor workability, because the add-on such as the memory card 133 or the like had to be loaded or unloaded through the narrow aperture 113a onto or out of the interface portion 130.
A first object of the present invention is to provide image forming apparatus that can enhance the loading/unloading workability of the add-on, prevent the electrical breakage of the interface portion, and ensure the user""s safety.
A second object of the present invention is to provide image forming apparatus comprising an interface portion for processing image information, power supply means for supplying power to the interface portion, an opening/closing member capable of opening or closing relative to a main body of the apparatus, and a cover capable of exposing the interface portion, wherein the supply of power from the power supply means to the interface portion is shut off in an open state of the opening/closing member and wherein opening of the cover is prohibited in a close state of the opening/closing member.
A third object of the present invention is to provide image forming apparatus comprising an interface portion for processing image information, power supply means for supplying power to the interface portion, an opening/closing member capable of opening or closing relative to a main body of the apparatus, and a cover capable of exposing the interface portion, wherein the supply of power from the power supply means to the interface portion is shut off in an open state of the opening/closing member and wherein closing of the opening/closing member is prohibited in an open state of the cover.
Further objects of the present invention will become apparent by the description which follows.